The Japanese coast guard has deployed 12 boats to exclusively patrol the region around the southwestern Senkaku islands over which Tokyo and Beijing have been embroiled in territorial disputes in recent years.
The coast guard on Monday said the fleet includes 10 patrol ships, each weighing 1,500 tonnes, and two vessels of Shikishima class, which are equipped with helicopters and each weighs 6,500 tonnes, making them the world's largest patrol boats after the Chinese CCG 3901, EFE news reported.
The 10 1,500-tonne vessels are equipped with 20-mm machine guns and the ability to cruise at high speeds.
Japan has decided to strengthen its military capacity on the Senkaku islands, known in China as Diaoyu, because of an escalation in disputes in recent years after Tokyo in 2012 nationalised several islets to the anger of Beijing.
Last week, Japan inaugurated a military base with a radar station on the Yonaguni island, the westernmost point of the Japanese archipelago, located 150 km south of the Senkaku islands.
Situated in the South China Sea, the Senkaku islands are uninhabited and have a total surface area of around 7 sq.km. They are believed to be rich in marine and energy resources.